A touch panel is an input device that allows a user to input user instructions directly with his fingers or a pointing object by selecting an icon displayed on the screen of an image display etc. When the user is touching the touch panel directly with his fingers or the pointing object, the touched points are detected by the touch panel and then the image display is driven in accordance with the instruction corresponding to the selected icon, thus achieving a specific display.
In accordance with the implementation principle, existing touch panels can be categorized mostly into capacitive touch panels and electromagnetic touch panels, wherein the capacitive touch panel identifies a touch operation from the received touch signal, i.e. an electrical signal, while the electromagnetic touch panel identifies a touch operation from the received signal, i.e. an electromagnetic signal from an electromagnetic pointer. Taking the self-capacitive touch panel, which is a kind of capacitive touch panel, as an example, it achieves the detection of the touched positions by fingers using a self-capacitive principle, which specifically comprises arranging in the touch panel multiple self-capacitive electrodes that are arranged in the same layer and separated from each other, wherein the capacitance achieved by each of the self-capacitive electrodes is of a fixed value when the screen is not touched by a human body, and the capacitance suffered by the self-capacitive electrode corresponding to a touched position is the fixed value plus the capacitance of a human body when the screen is touched by the human body; therefore, the touched positions can be recognized by a touch detecting chip during the touching period of time by detecting the change in the capacitance value of each self-capacitive electrodes. In practical implementation, the number of the self-capacitive electrodes is huge. For a self-capacitive electrode occupying an area of e.g. 5 mm*5 mm, a crystal liquid display of 5-inch requires 264 self-capacitive electrodes. In case an even smaller self-capacitive electrode is designed, more self-capacitive electrodes will be needed.
Therefore, the touch panel in the prior art is of a complex structure, which results in a complicated manufacture process and a higher cost.